Novel visible light-induced g-C3N4/Bi2WO6 composite photocatalysts for efficient degradation of methyl orange

Novel visible light-induced g-C3N4/Bi2WO6 composite photocatalysts were synthesized by introducing polymeric g-C3N4. The obtained g-C3N4/Bi2WO6 products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, ultraviolet–visible diffuse reflection spectroscopy (DRS), and photoluminescence spectroscopy. The DRS results revealed that the g-C3N4/Bi2WO6 samples had a red shift and strong absorption in the visible light region. The photocatalytic oxidation ability of the novel photocatalyst was evaluated using methyl orange as a target pollutant. The photocatalysts exhibited a significantly enhanced photocatalytic performance in degrading methyl orange. The optimal g-C3N4 content for the photocatalytic activity of the heterojunction structures was determined. The synergic effect between g-C3N4 and Bi2WO6 was found to lead to an improved photo-generated carrier separation. Consequently, the photocatalytic performance of the g-C3N4/Bi2WO6 composites under visible light irradiation (λ > 420 nm) was enhanced. The possible photocatalytic mechanism of the composites was proposed to guide the further improvement of their photocatalytic activity.

Novel visible light induced g-C3N4/Bi2WO6 heterojunction photocatalysts were synthesized by introducing polymeric g-C3N4 for the first time. The g-C3N4/Bi2WO6 samples showed the high efficiency for the photodegradation of methyl orange. The enhancement of photocatalytic performance of the g-C3N4/Bi2WO6 composite materials is attributed to the synergic effect between polymeric g-C3N4 and Bi2WO6 and effectively separation of photo-generated electron–hole pairs.Figure optionsDownload as PowerPoint slideHighlights
► Novel g-C3N4/Bi2WO6 heterojunction photocatalyst were prepared for the first time.
► The g-C3N4/Bi2WO6 showed remarkably enhanced photocatalytic activity.
► The arrangement and interfaces between g-C3N4 and Bi2WO6 were revealed by HRTEM.
► Photodegraded mechanism was proposed based on energy band positions.
► The mechanism was confirmed by PL spectra and photocatalytic results.